Students should have a knowledge of basic biological concepts typically covered during the first few months of an introductory biology course.

Teacher
instructions:

Keep in mind that this obituary was written in 1829! Review Lamarck's and Darwin's theories. Find many examples that seem to illustrate Lamarck's four laws and be able to explain the flaws in his reasoning. Before advancing to the work of Darwin explain how poor theories are replaced by better theories.

LONDON NEWS OBITUARIES

22 December 1829

Lamarck, French Naturalist, Is Dead!

Recent arrivals from Paris this week brought news that Jean Baptiste Pierre Antoine de Monet Lamarck died on the 18th of December 1829. A giant of French natural science, Lamarck was famous for his many contributions to biological thought.

Lamarck was born in the village of Bazantin in 1744, educated by the Jesuits at Amiens and decorated as a war hero at Bergenop-Zoom. He studied medicine in Paris while supporting himself by working in a bank office. His interests expanded to include meteorology, chemistry and botany. In 1778 he published Flore Française, an important work that popularized the use of dichotomous keys to identify plants. The great popularity and utility of this work brought him membership in the Academy of Sciences. In 1781 and 1782 he was botanist to the King; his close association with Buffon secured this position. Additional botanical works include the Dictionnaire de Botanique and Illustrations de Genres. In 1793 as a consequence of a reorganization at the Jardin du Roi, where he held a botanical appointment, his interests turned to zoology. As his interest in zoology grew many important works were published, in spite of the fact that be began to lose his sight and ultimately became totally blind.

All of Lamarck's endeavors were characterized by a breadth of knowledge, precise detail and a great ability to create systems of classification. Lamarck first saw animals as either vertebrates or invertebrates. Having made great contributions, it must, unfortunately, be recognized that at times his speculations regarding chemistry and meteorology were generally considered without value. For his flawed meteorological predictions he incurred the wrath of Napoleon in 1810.

Inspired by the earlier work of Buffon, Lamarck speculated on the origin of life. He accepted the theory of spontaneous generation. Under the influence of heat and electricity the whole of life formed from gelatinous bodies. Once having been created, organisms change according to four laws.

These are:

I.The steady increase in the volume of organisms and their parts.

II.The production of new organs is brought about by need or want.

III.The development of organs and their action depends on their being used.

IV.Acquired new organs, or changes in organization, are passed on to future generations.

His important second law, his hypothesis of evolution, explains the long neck of the giraffe, the slender legs of ruminants and the dwarfed front limbs of the kangaroo. The fourth law explains the passage of acquired characteristics to offspring.

Lamarck was truly a great man. It is difficult to imagine the growth of natural science without him. We are fortunate for his speculations regarding the origin of life and its subsequent evolution according to the four great laws. He has explained, for all, the origin and change of life on earth. We may all rest secure in this knowledge.

Questions for Further Thought

1.Give an example that seems to illustrate each of the four laws. Do not use the examples given above.

2.What became of Lamarck's four laws? Do we accept or use them today? Explain.